Adventure mode block data erase

block data...missing?

I thought i would get a normal ender chest (read below)

I made an enderchest with an NBT tag like this
/give MasterBuilder339 ender_chest 1 0

{CanPlaceOn:["34"]}

and placed it on a sticky piston head in adventure mode(/gamemode 2)

then I used my NBT tagged diamond pick with an NBT tag like this
/give MaterBuilder 339 diamond_pickaxe 1 0

{CanDestroy:["130"]}

with these enchants:
Silk Touch I
Unbeaking III
Sharpness v
Knockback II
and mined the NBT tagged ender chest and it was no longer NBT tagged!

Steps to Reproduce:
Do exactly what it says above